|
| |
|
|
A093420
|
|
Triangle read by rows: for 1 <= k <= n, numerator of a(n, k) = [prod_{i = 0..k-1} n-i]/[sum_{i = 1..k} i].
|
|
3
| |
|
|
1, 2, 2, 3, 2, 1, 4, 4, 4, 12, 5, 20, 10, 12, 8, 6, 10, 20, 36, 48, 240, 7, 14, 35, 84, 168, 240, 180, 8, 56, 56, 168, 448, 960, 1440, 1120, 9, 24, 84, 1512, 1008, 2880, 6480, 10080, 8064, 10, 30, 120, 504, 2016, 7200, 21600, 50400, 80640, 725760, 11, 110, 165
(list; table; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
COMMENTS
| a(n, n) = 2*(n-1)!/(n+1).
A093421 gives the denominators.
|
|
|
CROSSREFS
| Cf. A093412, A093421, A093422.
Sequence in context: A162915 A092565 A021452 * A104897 A185694 A097510
Adjacent sequences: A093417 A093418 A093419 * A093421 A093422 A093423
|
|
|
KEYWORD
| nonn,easy,frac,tabl,less
|
|
|
AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Mar 30 2004
|
|
|
EXTENSIONS
| Edited and extended by David Wasserman (dwasserm(AT)earthlink.net), Aug 29 2006
|
| |
|
|